Item queries for single entities

Efficient caching lets you deliver content quickly and improves the overall user experience. When fetching single entities in Optimizely Graph, you can significantly enhance cache hit ratios by strategically using item queries instead of items in GraphQL.

Understand the cache challenge

GraphQL's flexibility can lead to queries that fetch lists of items using items. While useful in many scenarios, this approach can reduce caching efficiency. Even if a query returns only a single item, using items requires refreshing the entire list's cache when any item changes. This broad cache invalidation lowers performance compared to more targeted caching.

Benefit of item

The item query lets you implement precision caching by focusing on a single item using its unique identifier. When an item changes, only its cache entry updates instead of refreshing the entire list's cache. This improves caching efficiency and boosts performance.

Example of an item query

The following code sample demonstrates an item query that retrieves a single item based on its RelativePath:

query GetItem($relativePath: String) {  
  Content(where: { RelativePath: { eq: $relativePath } }) {  
    item { Name RelativePath }  
  }  
}

Optimize cache with item

• Improve cache hit ratio withitem – Using item queries improves cache efficiency by enabling more precise caching. Instead of refreshing the entire list, the cache updates only the specific item. This increases the likelihood of receiving up-to-date data for frequently accessed items.
• Unique identifier-driven queries – Use item only when retrieving a single item based on unique identifiers such as the following:
  • Relative paths
  • URLs
  • Segments
  • Code
  • Any other uniquely identifiable field for the desired item.
• ID-based caching and purging – The GraphQL server caches the result of your item query using the returned id of the fetched item. This approach ensures the system only purges the cached result when that specific item is republished with changes. As a result, if other items are updated, your cached item result remains valid, maximizing cache hits.